Great work! Hacky but great! I'm also new to PW but I'm loving it so far.
My solution for using MenuBuilder with Bootstrap 3 is kinda hacky as well. No need to change the module code here but it's definitely some sloppy coding, like don't-try-this-at-home-sloppy.
Configure the options like so:
$options = array(
'wrapper_list_type' => 'ul',
'menu_css_class' => 'nav navbar-nav',
'submenu_css_class' => 'dropdown-menu',
'has_children_class' => 'dropdown',
);
And do the rest with jQuery: (the sloppy part)
$(document).ready(function () {
$(".dropdown [href='#']:first-child").attr("data-toggle", "dropdown").addClass('dropdown-toggle');
});
I know the the dropdowns are selected with [href=#] (which is horrible). I did that because reasons. It works. And it took only 30 minutes to figure out. That proofs how awesome this module is!